Background and Aims:
Results from studies on APOE genotype and ischemic stroke (IS) outcome are conflicting. We evaluated whether APOE associates with IS outcome, severity and age at onset, within a large international meta-analysis; the Genetics of Ischaemic Stroke Functional Outcome (GISCOME).
Methods:
This study comprises 6,165 patients within GISCOME with information on modified Rankin Scale (mRS) score at 3 months post-stroke. We derived APOE allele status (ε2, ε3, ε4) by combining information on the minor alleles of single nucleotide polymorphisms rs7412 and rs429358. Effects of ε4 and ε2 on outcome (dichotomized as mRS>2 versus mRS ≤2 and ordinal
analysis of the full mRS scale), age and stroke severity (baseline NIHSS) were estimated separately in comparison to the most common ε3/ε3 genotype.
Results:
We found no evidence of association between the ε4 allele and IS outcome, adjusting for age and severity (P>0.21 for both dichotomized and ordinal mRS). There was, however, an inverse association between the ε4 allele and age at stroke (adjusted β -1.8, P=0.00017). This association was significant in both sexes. The ε2 allele was independently associated with poor functional outcome (mRS>2) in men (odds ratio [OR] 1.47, P=0.008), but not in women (OR
0.87, P=0.44).
Conclusions:
This is the largest meta-analysis on APOE genotype and IS outcome to our knowledge. We found a lower age at stroke onset in ε4 carriers and a worse functional outcome in male ε2 carriers. Even larger studies are warranted to further investigate the effects of APOE alleles on IS outcome in different age and sex strata.

2 - APOLIPOPROTEIN E Ε4 ASSOCIATES TO AGE OF ISCHEMIC STROKE ONSET BUT NOT TO FUNCTIONAL OUTCOME